Sewing device

ABSTRACT

Means for use in template-controlled sewing devices in which a magnetic roller rolls along the peripheral edge of the template, for preventing a recoil of the roller out of the internal corner of the template when said roller reaches the corner with a proportional high speed. The means consist of a supporting body which carries the workpiece clamping means and the template and which rests on the support means slidable in a horizontal plane and under the own weight. Furthermore, there are provided adjustable shock absorbers and means for returning the supporting body into a predetermined normal position after terminating a sewing cycle.

United States Patent 1191 11] 3,869,998 Scholl Mar. 11, 1975 [54] SEWING DEVICE 2,926,881 3/1960 Painter 248/358 R 3,182,616 5/1965 Cremer ..ll2/12l.l2 [751 lnvenmr- 5cm", 3,682,! 19 8/1972 Junemann 112/121.14

Oerlmghausen-lnpperrethe, Germany Primary Examiner-Werner H. Schroeder [73] Assignee: Kochs Adler AG, Bielefeld, Attorney, Agent, or Firm-Jacob L. Kollin Germany [22 Filed: May 10, 1973 ABSTRACT [2]] Appl NOJ 358,840 Means for use in template-controlled sewing devices in which a magnetic roller rolls along the peripheral edge of the template, for preventing a recoil of the rol- 1 Foreign Appllcatlon P710111) Data ler out of the internal corner of the template when May 10, 1972 Germany 2222846 said roller reaches the corner with a proportional high speed. [52] US. Cl. 1l2/l2l.l5 The means consist of a supporting body Which carries [51] Int. Cl D05b 21/00 the workpiece clamping means and the template and [58] Field of Search..... 112/121.12, 121.15, 121.14, which rests on h Support means Slidable i a ll2/258, 260; 248/358 R, 22; 74/567 568 R horizontal plane and under the own weight. Furthermore, there are provided adjustable shock [56] References C'ted absorbers and means for returning the supporting UNITED STATES PATENTS body into a predetermined normal position after 804,884 11/1905 Rutan 112/258 x e minating a sewing cycle. 2,046,939 7/1936 Edwards 112/258 4 Cl 5 D 11/1947 De Vorss, Jr. 248/358 R 'awmg V SEWING DEVICE BACKGROUND OF THE INVENTION The invention relates to a sewing device which is provided with a support, a sewing machine swingably in a horizontal plane and carried by the support, a template having internal corners, workpiece clamping means above the plate, a supporting body carrying the template and the workpiece clamping means, and a motor driven magnetic roller coaxially with the needle of the sewing machine and bearing against the template.

In a sewing device of the above mentioned kind the sewing machine and the linkages which carry and lead the sewing machine, form a large mass. In this case it is necessary to reduce the speed of the magnetic roller when it enters an internal corner of the template to avoid a reflecting of the same an the sewing machine.

It is a primary object of the invention to provide a template controlled sewing device with a mechanism which causes an uniform speed of the magnetic roller when entering an internal corner of the template.

A further object of the invention is to avoid an interruption of the feed of the magnetic roller when it arrives at an internal corner of the template with a high speed.

SUMMARY OF THE INVENTION According to the invention the above problems are solved by a supporting body which carries the workpiece clamping means and the template and which rests on the support of the sewing device under the own weight and slidable in a horizontal plane. There are further provided limiting means for the localization of the displaccability of the supporting body on the support and adjustable shock absorbers mounted between the support and the supporting body and acting in a horizontal plane. Furthermore, there are provided means for returning the supporting body resting on the support, into a predetermined normal position after terminating a sewing cycle.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a top plane view of the sewing device, FIG. 2 is a side elevation of the sewing device, FIG. 3 is a section taken along line III III of FIG. I,

FIG. 4 is a section taken along line IV IV of FIG. 1 and FIG. 5 is a perspective view of the supporting body resting on the support of the sewing device, seen from the left and in an enlarged scale.

DESCRIPTION OF THE PREFERRED EMBODIMENT On two side panels 1, which are screwed to a connecting beam 2 and are belonging to the support 1 of the sewing device, is displaceably supported a supporting body 3, comprising an hollow rail 4, a supporting plate 5 for a template 6, a workpiece clamping holder 7 and sliding plates 8. The sliding plates 8 are secured via connecting rails 9 to the hollow rail 4 by means of screws 10.

A driven magnetic roller 13 arranged in a supporting arm 15 which carries a sewing machine 14, engages with the peripheral edge llof the template 6, which is screwd to the supporting plate 5 (FIGS. 1 and 2) by means of distance bolts 12.

Pivoted to the support 1 is a swivel arm 17 connected via a connecting arm 18 to the supporting arm 15. The supporting arm 15 supporting the sewing machine 14, is guided by a not further shown device in such a manner, that it maintains a nearly vertically extending position with regard to the hollow rail 4 while moving in accordance with the course of the peripheral edge 11 of the template 6.

Mounted to the connecting beam 2 is a combined inserting and removing device 19 serving for inserting workpieces 20 consisting of several layers, into the workpiece clamping holder 7, which is located on the supporting plate 5 carried by posts 23, and for removing a workpiece 22 provided with a seam 21, out of the workpiece clamping holder 7.

Both ends of the hollow rail 4 of the supporting body 3 are displaceably carried on a plane surface 24 of the side panels 1, while the sliding plates 8 connected to the hollow rail 4 by means of connecting rails 9, rest on an intermediate plate 25 provided with limiting means 26. The latter comprise back stops 28, received with a lateral clearance in circular recesses 29 provided in the sliding plates 8, washers 30 lying on the back stops 28 and having a larger diameter than the circular recesses 29. The washers 30, the back stops 28 and the intermediate plates are screwed to the side panels 1 by means of screws 27 and nuts 31. As the back stops 28 have a larger dimension of height than the sliding plates 8, they may be displaced and the entire supporting body as well, within the range limited by the lateral clearance between the back stops 28 and the recesses 29.

Arranged to each side panel 1' of the support 1 is a shock absorber 32 composed by a cylindrical bolt 33 (FIG. 3) provided with a threaded end 34 and screwed by means ofa nut 35 to the side panels 1', and a lower thrust washer 36 formed with a threaded sleeve 37, an upper thrust washer 38, a pressure spring 39, a washer 40 and adjusting and locking nuts 41.

The lower thrust washer 36 received in a recess 42 provided in the intermediate plate 25, is secured against torsion by means of a pin 43 inserted in the side panels 1', and a slot 44 provided in the thrust washer 36. The sliding plate 8 is formed with a recess 45, in which is received the threaded sleeve 37 with a lateral clearance. By means of the adjusting and locking nuts 41 located on the threaded sleeve 37, the pressure spring 39 may be tensioned in order to press both thrust washers 36, 38 against the sliding plate 8 with the required tension.

A device for returning the displaced supporting body 3 into its predetermined normal position is provided at the intermediate plates 25 (FIGS. 1, 4 and 5). This device has a double acting air cylinder 47, the piston rod 48 of which is guided in a guide piece 49, which is secured together with the air cylinder 47 to the intermediate plate 25 by means of screws 50. On the piston rod 48 projecting with a radial clearance through a coneshaped recess 52 formed in the supporting body 3, is located a cone-shaped centering device 51.

Operation of the device may be described as follows:

When the magnetic roller 13 is following the template 6, there may occur in particular in those corners of the template (for instance in the corner denoted with E in FIG. 1) backstrokes depending on the driving speed of the magnetic roller 13 and the masses to be decelerated and which cause stitch failures.

As a consequence of the supporting body 3 receiving the template 6 and the workpiece clamping holder 7, and movable in a horizontal plane opposed to the support 1, and by means of the adjustable shock absorbers 32 these backstrokes may be damped in such a manner, that the magnetic roller 13 does not leave the template 6 even at a relatively high driving speed.

After termination of sewing, the displaced supporting body 3 must be returned into its normal position in order that the workpiece to be inserted into the workpiece clamping holder 7 by means of the inserting device 19, is received therein with a seam edge projecting uniformly from the clamping plates of the workpiece clamping holder 7. This normal position is obtained by means of the device for returning 46 by pressurizing the air cylinder 47 causing that the coneshaped centering device 51 is drawn into the coneshaped recess 52 formed in the sliding plate 8 of the supporting body 3, and the supporting body 3 and the workpiece clamping holder 7 are brought into a determined position with regard to the inserting device 19.

What we claim is:

1. In a sewing device with guided control of a sewing cycle, comprising a support means, a link arm, means swingably attaching said link arm to said support means. a supporting arm, a connecting arm pivoted on said link arm and said supporting arm, a template having internal corners, workpiece clamping means above said template, a driven magnetic roller engaged with the peripheral edge of said template, means attaching said magnetic roller on said supporting arm, a sewing machine carried by said supporting arm and having a vertically reciprocating needle coaxially with the said magnetic roller, and a supporting body carrying said workpiece clamping means and said template, shock absorbing means between said supporting body and said supporting means for limiting said supporting body to slide with respect to said support means when said template receives a relatively high shock by having said magnetic roller slam into an internal corner, said shock-absorbing means comprising an upper thrust washer having a bore, a lower thrust washer provided with a threaded sleeve for receiving said upper thrust washer, a spring for pressing said thrust washers against said supporting body, a bolt secured to said support means for slidably receiving said threaded sleeve, regulating nuts on said bolts for adjusting the tension of said spring and a recess formed in said supporting body for receiving said threaded sleeve.

2. A device as claimed in claim 1, further comprising means for returning said supporting body displaced by said high shock into a predetermined normal position after terminating a sewing cycle.

3. A device as claimed in claim 2, wherein each of said means for returning said supportingbody comprises an air cylinder having a piston rod and fastened to said support means, a cone shaped recess formed in said supporting body and surrounding said piston rod,

' and a cone shaped centering device fastened to said piston rod and cooperating with said cone sahped recess when said air cylinder is charged.

4. In a sewing device as claimed in claim 3, wherein said limiting means comprises back stops fastened to said support means and received in recesses formed in said supporting body. 

1. In a sewing device with guided control of a sewing cycle, comprising a support means, a link arm, means swingably attaching said link arm to said support means, a supporting arm, a connecting arm pivoted on said link arm and said supporting arm, a template having internal corners, workpiece clamping means above said template, a driven magnetic roller engaged with the peripheral edge of said template, means attaching said magnetic roller on said supporting arm, a sewing machine carried by said supporting arm and having a vertically reciprocating needle coaxially with the said magnetic roller, and a supporting body carrying said workpiece clamping means and said template, shock absorbing means between said supporting body and said supporting means for limiting said supporting body to slide with respect to said support means when said template receives a relatively high shock by having said magnetic roller slam into an internal corner, said shock-absorbing means comprising an upper thrust washer having a bore, a lower thrust washer provided with a threaded sleeve for receiving said upper thrust washer, a spring for pressing said thrust washers against said supporting body, a bolt secured to said support means for slidably receiving said threaded sleeve, regulating nuts on said bolts for adjusting the tension of said spring and a recess formed in said supporting body for receiving said threaded sleeve.
 1. In a sewing device with guided control of a sewing cycle, comprising a support means, a link arm, means swingably attaching said link arm to said support means, a supporting arm, a connecting arm pivoted on said link arm and said supporting arm, a template having internal corners, workpiece clamping means above said template, a driven magnetic roller engaged with the peripheral edge of said template, means attaching said magnetic roller on said supporting arm, a sewing machine carried by said supporting arm and having a vertically reciprocating needle coaxially with the said magnetic roller, and a supporting body carrying said workpiece clamping means and said template, shock absorbing means between said supporting body and said supporting means for limiting said supporting body to slide with respect to said support means when said template receives a relatively high shock by having said magnetic roller slam into an internal corner, said shock-absorbing means comprising an upper thrust washer having a bore, a lower thrust washer provided with a threaded sleeve for receiving said upper thrust washer, a spring for pressing said thrust washers against said supporting body, a bolt secured to said support means for slidably receiving said threaded sleeve, regulating nuts on said bolts for adjusting the tension of said spring and a recess formed in said supporting body for receiving said threaded sleeve.
 2. A device as claimed in claim 1, further comprising means for returning said supporting body displaced by said high shock into a predetermined normal position after terminating a sewing cycle.
 3. A device as claimed in claim 2, wherein each of said means for returning said supporting body comprises an air cylinder having a piston rod and fastened to said support means, a cone shaped recess formed in said supporting body and surrounding said piston rod, and a cone shaped centering device fastened to said piston rod and cooperating with said cone sahped recess when said air cylinder is charged. 